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#include "AABBTri.h"



#define X 0

#define Y 1

#define Z 2


#define CROSS(dest,v1,v2)\
dest[0]=v1[1]*v2[2]-v1[2]*v2[1];\
	dest[1]=v1[2]*v2[0]-v1[0]*v2[2];\
	dest[2]=v1[0]*v2[1]-v1[1]*v2[0]; 



#define DOT(v1,v2) (v1[0]*v2[0]+v1[1]*v2[1]+v1[2]*v2[2])



#define SUB(dest,v1,v2) \
dest[0]=v1[0]-v2[0]; \
	dest[1]=v1[1]-v2[1]; \
	dest[2]=v1[2]-v2[2]; 



#define FINDMINMAX(x0,x1,x2,min,max) \
min = max = x0;   \
	if(x1<min) min=x1;\
		if(x1>max) max=x1;\
			if(x2<min) min=x2;\
				if(x2>max) max=x2;


int planeBoxOverlap(float normal[3], float vert[3], float maxbox[3])	// -NJMP-

{

	int q;

	float vmin[3],vmax[3],v;

	for(q=X;q<=Z;q++)

	{

		v=vert[q];					// -NJMP-

		if(normal[q]>0.0f)

		{

			vmin[q]=-maxbox[q] - v;	// -NJMP-

			vmax[q]= maxbox[q] - v;	// -NJMP-

		}

		else

		{

			vmin[q]= maxbox[q] - v;	// -NJMP-

			vmax[q]=-maxbox[q] - v;	// -NJMP-

		}

	}

	if(DOT(normal,vmin)>0.0f) return 0;	// -NJMP-

	if(DOT(normal,vmax)>=0.0f) return 1;	// -NJMP-



	return 0;

}





/*======================== X-tests ========================*/

#define AXISTEST_X01(a, b, fa, fb)			   \
p0 = a*v0[Y] - b*v0[Z];			       	   \
	p2 = a*v2[Y] - b*v2[Z];			       	   \
	if(p0<p2) {min=p0; max=p2;} else {min=p2; max=p0;} \
		rad = fa * boxhalfsize[Y] + fb * boxhalfsize[Z];   \
		if(min>rad || max<-rad) return 0;



#define AXISTEST_X2(a, b, fa, fb)			   \
p0 = a*v0[Y] - b*v0[Z];			           \
	p1 = a*v1[Y] - b*v1[Z];			       	   \
	if(p0<p1) {min=p0; max=p1;} else {min=p1; max=p0;} \
		rad = fa * boxhalfsize[Y] + fb * boxhalfsize[Z];   \
		if(min>rad || max<-rad) return 0;



/*======================== Y-tests ========================*/

#define AXISTEST_Y02(a, b, fa, fb)			   \
p0 = -a*v0[X] + b*v0[Z];		      	   \
	p2 = -a*v2[X] + b*v2[Z];	       	       	   \
	if(p0<p2) {min=p0; max=p2;} else {min=p2; max=p0;} \
		rad = fa * boxhalfsize[X] + fb * boxhalfsize[Z];   \
		if(min>rad || max<-rad) return 0;



#define AXISTEST_Y1(a, b, fa, fb)			   \
p0 = -a*v0[X] + b*v0[Z];		      	   \
	p1 = -a*v1[X] + b*v1[Z];	     	       	   \
	if(p0<p1) {min=p0; max=p1;} else {min=p1; max=p0;} \
		rad = fa * boxhalfsize[X] + fb * boxhalfsize[Z];   \
		if(min>rad || max<-rad) return 0;

/*======================== Z-tests ========================*/

#define AXISTEST_Z12(a, b, fa, fb)			   \
p1 = a*v1[X] - b*v1[Y];			           \
	p2 = a*v2[X] - b*v2[Y];			       	   \
	if(p2<p1) {min=p2; max=p1;} else {min=p1; max=p2;} \
		rad = fa * boxhalfsize[X] + fb * boxhalfsize[Y];   \
		if(min>rad || max<-rad) return 0;



#define AXISTEST_Z0(a, b, fa, fb)			   \
p0 = a*v0[X] - b*v0[Y];				   \
	p1 = a*v1[X] - b*v1[Y];			           \
	if(p0<p1) {min=p0; max=p1;} else {min=p1; max=p0;} \
		rad = fa * boxhalfsize[X] + fb * boxhalfsize[Y];   \
		if(min>rad || max<-rad) return 0;



int triBoxOverlap(float boxcenter[3],float boxhalfsize[3],float triverts[3][3])

{



	/*    use separating axis theorem to test overlap between triangle and box */

	/*    need to test for overlap in these directions: */

	/*    1) the {x,y,z}-directions (actually, since we use the AABB of the triangle */

	/*       we do not even need to test these) */

	/*    2) normal of the triangle */

	/*    3) crossproduct(edge from tri, {x,y,z}-directin) */

	/*       this gives 3x3=9 more tests */

	float v0[3],v1[3],v2[3];

	//   float axis[3];

	float min,max,p0,p1,p2,rad,fex,fey,fez;		// -NJMP- "d" local variable removed

	float normal[3],e0[3],e1[3],e2[3];



	/* This is the fastest branch on Sun */

	/* move everything so that the boxcenter is in (0,0,0) */

	SUB(v0,triverts[0],boxcenter);

	SUB(v1,triverts[1],boxcenter);

	SUB(v2,triverts[2],boxcenter);



	/* compute triangle edges */

	SUB(e0,v1,v0);      /* tri edge 0 */

	SUB(e1,v2,v1);      /* tri edge 1 */

	SUB(e2,v0,v2);      /* tri edge 2 */



	/* Bullet 3:  */

	/*  test the 9 tests first (this was faster) */

	fex = fabsf(e0[X]);

	fey = fabsf(e0[Y]);

	fez = fabsf(e0[Z]);

	AXISTEST_X01(e0[Z], e0[Y], fez, fey);

	AXISTEST_Y02(e0[Z], e0[X], fez, fex);

	AXISTEST_Z12(e0[Y], e0[X], fey, fex);



	fex = fabsf(e1[X]);

	fey = fabsf(e1[Y]);

	fez = fabsf(e1[Z]);

	AXISTEST_X01(e1[Z], e1[Y], fez, fey);

	AXISTEST_Y02(e1[Z], e1[X], fez, fex);

	AXISTEST_Z0(e1[Y], e1[X], fey, fex);



	fex = fabsf(e2[X]);

	fey = fabsf(e2[Y]);

	fez = fabsf(e2[Z]);

	AXISTEST_X2(e2[Z], e2[Y], fez, fey);

	AXISTEST_Y1(e2[Z], e2[X], fez, fex);

	AXISTEST_Z12(e2[Y], e2[X], fey, fex);



	/* Bullet 1: */

	/*  first test overlap in the {x,y,z}-directions */

	/*  find min, max of the triangle each direction, and test for overlap in */

	/*  that direction -- this is equivalent to testing a minimal AABB around */

	/*  the triangle against the AABB */



	/* test in X-direction */

	FINDMINMAX(v0[X],v1[X],v2[X],min,max);

	if(min>boxhalfsize[X] || max<-boxhalfsize[X]) return 0;



	/* test in Y-direction */

	FINDMINMAX(v0[Y],v1[Y],v2[Y],min,max);

	if(min>boxhalfsize[Y] || max<-boxhalfsize[Y]) return 0;



	/* test in Z-direction */

	FINDMINMAX(v0[Z],v1[Z],v2[Z],min,max);

	if(min>boxhalfsize[Z] || max<-boxhalfsize[Z]) return 0;



	/* Bullet 2: */

	/*  test if the box intersects the plane of the triangle */

	/*  compute plane equation of triangle: normal*x+d=0 */

	CROSS(normal,e0,e1);

	// -NJMP- (line removed here)

	if(!planeBoxOverlap(normal,v0,boxhalfsize)) return 0;	// -NJMP-



	return 1;   /* box and triangle overlaps */

}


